1. Field of the Invention
The present invention relates generally to fluid flow apparatus and more particularly, to apparatus for introducing a secondary fluid into a primary fluid system.
2. Description of the Related Art
The prior art includes various examples of apparatus for the mixing of the fluid streams, included among which are the following U.S. Patents.
U.S. Pat. No. 907,851 to Munson discloses a flume gate in which a movable gate is mounted in a gate holder which includes cylindrical springs. The flume gate can be moved to adjust the flow through the flume.
U.S. Pat. No. 2,968,919 to Hughes et al discloses a variable area nozzle in which circumferentially spaced vanes are provided in a nozzle throat. The position of the vanes can be adjusted to restrict the flow of fluid through the nozzle in response to changes in pressure upstream from the throat.
U.S. Pat. No. 4,087,862 to Tsein discloses a bladeless mixing device in which streams are tangentially directed into an inlet mixing chamber in which a converging vortex is created which passes through an orifice into an outlet mixing chamber in which a diverging vortex is created. The stream leaves the outlet mixing chamber in a tangential direction for subsequent passage through further stages of the mixing device which include additional inlet and outlet mixing chambers.
U.S. Pat. No. 4,103,351 to Mamvriisky discloses an apparatus for controlling the density of a plugging fluid for oil and gas wells which includes an orifice which is rotatable about its longitudinal axis in the area of mixing a dry cementation material. The orifice produces a flat jet stream which rotates and mixes the dry cementation material.
U.S. Pat. No. 4,123,800 to Mazzei discloses a mixer-injector apparatus in which a throat portion having a portion of decreasing and increasing diameter is disposed between a carrier stream inlet and outlet. A port discharges additive fluid into the throat portion.
U.S. Pat. No. 4,415,275 to Dietrich discloses a swirl mixing device in which a first injector injects a first fluid into a first injection chamber and a second injector injects a second fluid into a second injector chamber. The two fluids have opposite angular momentum and meet near an opening in a collar separating the two chambers.
U.S. Pat. No. 4,552,178 to Olsson discloses a variable fluid flow restricting throttle device in which a pair of members are rotatably connected in a fluid-tight relationship and each of which includes a plurality of fluid flow openings. The members may be rotated to selectively align the fluid flow openings to create varying flow paths of varying diameters.
U.S. Pat. No. 5,061,406 to Cheng discloses an apparatus for in-line dispersion of a gas in a liquid which includes an adjustable conical mixer to control the flow of a gas.backslash.liquid mixture to a venturi device. The venturi device is used to accelerate the mixtures to a supersonic velocity with subsequent deceleration to subsonic velocity to produce shock waves in the mixture.
U.S. Pat. No. 5,230,254 to Blough. Jr. et al discloses a fluid mixing device which includes a mixing chamber and four fluid conduits which join the mixing chamber at predetermined angles to introduce fluids into the mixing chamber and create a rapid vortexing action.
U.S. Pat. No. 5,573,334 to Anderson discloses a method for the turbulent mixing of gases in which a first gas flowing from a first orifice in a tubular housing is directed at a second gas flowing from a second orifice. The two orifices are offset so as to produce a swirling action within the tubular housing.
Although the prior art includes various examples of devices intended to introduce a secondary fluid into a stream of primary fluid, there still remains a need for an apparatus which can both introduce the secondary fluid into the stream of primary fluid and control the flow of secondary fluid in a simple and effective manner.